China (Mainland)
competitive price Silver 7440-22-4 CAS NO.7440-22-4
- Min.Order: 1 Kilogram
- Payment Terms: T/T,Other
- Product Details
Keywords
- 7440-22-4
- Silver
- Ag
Quick Details
- ProName: competitive price Silver 7440-22-4
- CasNo: 7440-22-4
- Molecular Formula: Ag
- Appearance: detailed see specifications
- Application: Silver and its alloys and compounds ha...
- DeliveryTime: within 3 days
- PackAge: as customer's request
- Port: Shanghai/Qingdao
- ProductionCapacity: 1 Kilogram/Day
- Purity: 97%-99%
- Storage: 2-8°C
- Transportation: By sea/car
- LimitNum: 1 Kilogram
Superiority
Henan CoreyChem Co., Ltd, based on the original Zhengzhou Cote Chemical Research Institute, be brave in absorbing highly educated talents & overseas returnees; actively responded to Zhengzhou City High-tech Zone Government’s Special Care Policy, reorganized and founded in National University of Science and Technology Park, which is a high-tech, stock enterprise of high-end chemical Custom synthesis;The park was created by the People's Government of Henan Province, and proved by Ministry of Education and the National Science & Technology, taking the construction mode of "many college a park, and common development", mainly depends on Zhengzhou University and Henan University’s scientific research and talent advantage to set up Universities, scientific research institute and enterprise scientific research achievements transformation platform, to make high-tech enterprises incubate, is the new high-tech talent gathering base, high and new technology industry enterprise radiation base, colleges and universities technological innovation base.
Henan Coreychem Co., Ltd, facing global High-tech pharmaceutical raw materials, high complex new type intermediates, fine chemicals custom synthesis, scale-up production and Rare chemicals trade. Corey have well-equipped machine, strong technical force and considerate marketing team service. We also have rich experience advantage in basic research, small scale process development, scale-up, industrial technology development & production and cost control.
Our R&D center building area is 811 square meters, with 3 contributing proffesor of technical advisor, 4 Dr., 10 masters, and 28 research staff. Our level of chemical synthesis is known to the industry. So we have accumulated rich experience in synthetic methods design and exploring the synthesis of new technology. Not only we are good in heterocyclic chemistry, chiral chemistry (asymmetric synthesis and enzyme reactions), metal organic synthesis, high throughput chemistry, also specializes in bioorganic chemistry, including nucleosides, nucleotides, sugar chemistry, peptide chemistry. R & D center has many sets of 10 liters, 20 liters, 50 liters, 100L multifunction high and low pressure reaction still, rotary evaporator, anhydrous anaerobic reaction devices, hydrogenation equipment, cryogenic process (-120 degrees) equipment, to complete mg level custom synthesis and kg level process development experiments. The Existing 600M NMR, LCMS, Fourier Infrared Spectrometer, liquid chromatography, differentialscanning calorimetry, and other advanced detection equipment areto ensure quality and efficient completion of R&D projects. So far our completed custom synthesis products is more than 5300 species, where dozens of them are non-CAS declaration products, almost including all types of organic reactions.
At present, in addition to our headquarters in Zhengzhou, we also have another product base in Jun County, Henan Province. This base is the attracting investment of science and technology project of Jun County govenment’s, which covers 6529 square meters. In addition to bear our own company’s 1000L-5000L pilot task, also bear the function of Henan pilot incubation service platform, In order to improve Henan and surroundings’ synthetic reaction pilot service ability and the key technology development capabilities. Base with three GMP standards workshop, a testing center, one test center,one experiment center and associatd supporting facilities, can carry out oxidation, hydrogenation (70 kg pressure), halogenated, acieration, etherification, condensation, cyclization, formatting, ammoniated, diazotization andpilot service such as azide reactions etc. In the future we will work hard to make it become the most complete production system in central China and even the whole country, the highest technical level, the strongest talent team, the most popular service scope of pilot incubation service platform.
Henan Coreychem co., LTD. is committed to provide cost effective chemical service to the global fine chemical industry product development agencies; we adhering to the consistent good commercial reputation, to create a highly efficient, high quality of chemical research, development, production, sales and service of integrated platform, let our customers faster, better get ideal and thoughtful service.
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Henan CoreyChem Co., Ltd, based on the original Zhengzhou Cote Chemical Research Institute, be brave in absorbing highly educated talents & overseas returnees; actively responded to Zhengzhou City High-tech Zone Government’s Special Care Policy, reorganized and founded in National University of Science and Technology Park, which is a high-tech, stock enterprise of high-end chemical Custom synthesis;The park was created by the People's Government of Henan Province, and proved by Ministry of Education and the National Science & Technology, taking the construction mode of "many college a park, and common development", mainly depends on Zhengzhou University and Henan University’s scientific research and talent advantage to set up Universities, scientific research institute and enterprise scientific research achievements transformation platform, to make high-tech enterprises incubate, is the new high-tech talent gathering base, high and new technology industry enterprise radiation base, colleges and universities technological innovation base.
Details
| Silver Basic information |
| Silver Chemical Properties |
| Melting point | 960 °C(lit.) |
| Boiling point | 2212 °C(lit.) |
| density | 1.135 g/mL at 25 °C |
| vapor density | 5.8 (vs air) |
| vapor pressure | 0.05 ( 20 °C) |
| refractive index |
n |
| Fp | 232 °F |
| storage temp. | 2-8°C |
| solubility | H2O: soluble |
| form | wool |
| color | Yellow |
| Specific Gravity | 10.49 |
| Odor | Odorless |
| resistivity | 1-3 * 10^-5 Ω-cm (conductive paste) &_& 1.59 μΩ-cm, 20°C |
| Water Solubility | insoluble |
| Sensitive | Light Sensitive |
| Merck | 13,8577 |
| Exposure limits | TLV-TWA (metal dusts and fumes) 0.1 mg/m3 (ACGIH), 0.01 mg/m3 (MSHA and OSHA), soluble compounds 0.01 mg/m3 (AIGIH). |
| Stability: | Stable. Substances to be avoided include strong acids and strong bases, tartaric acid, oxalic acid. Blackened by contact with ozone, hydrogen sulfide, sulfur. Powder is highly flammable. |
| CAS DataBase Reference | 7440-22-4(CAS DataBase Reference) |
| NIST Chemistry Reference | Silver(7440-22-4) |
| EPA Substance Registry System | Silver(7440-22-4) |
| Safety Information |
| Hazard Codes | N,Xn,T,Xi,F |
| Risk Statements | 22-38-20/21-10-40-34-23/24/25-36/37/38-67-36-11-50/53-36/38 |
| Safety Statements | 26-24/25-25-45-36/37/39-23-16-7-61 |
| RIDADR | UN 3264 8/PG 3 |
| WGK Germany | 3 |
| RTECS | VW3500000 |
| F | 8 |
| TSCA | Yes |
| HazardClass | 6.1 |
| PackingGroup | III |
| HS Code | 71069110 |
| Hazardous Substances Data | 7440-22-4(Hazardous Substances Data) |
| Toxicity |
PEL (OSHA) 0.01 mg/m3 TLV-TWA (ACGIH) 0.1 mg/m3 (silver metal) TLV-TWA (ACGIH) 0.01 mg/m3 (soluble silver compounds, as Ag) |
| MSDS Information |
| Provider | Language |
|---|---|
| C.I. 77820 | English |
| ACROS | English |
| SigmaAldrich | English |
| ALFA | English |
| Silver Usage And Synthesis |
| History | Silver is one of the oldest metals, known since ancient times. It is a precious metal worldwide, used in ornaments, coins, and utensils. The symbol Ag for this element is derived from the Latin word, argentum. Silver occurs in nature in native form, commonly associated with gold. It is found in most lead and copper ores. The principal mineral of silver is argentite, Ag2S [1332-04-3]. Some other silver minerals include pyrargyrite, Ag3SbS3 [15123-77-0]; proustite, Ag3AsS3 [15152-58-4]; polybasite, Ag16Sb2S11 [53810-31-4]; cerargyrite, AgCl [14358-96-4]; stephanite, Ag5SbS4 [1302-12-1]; and tetrahedrite, Cu3(AsSb)S3. Abundance of silver in the earth’s crust is estimated to be 0.075 mg/kg and its average concentration in sea water is 0.014 µg/L. |
| Uses |
Silver and its alloys and compounds have numerous applications. As a precious metal, silver is used in jewelry. Also, one of its alloys, sterling silver, containing 92.5 weight % silver and 7.5 weight % copper, is a jewelry item and is used in tableware and decorative pieces. The metal and its copper alloys are used in coins. Silver-copper brazing alloys and solders have many applications. They are used in automotive radiators, heat exchangers, electrical contacts, steam tubes, coins, and musical instruments. Some other uses of silver metal include its applications as electrodes, catalysts, mirrors, and dental amalgam. Silver is used as a catalyst in oxidation-reductions involving conversions of alcohol to aldehydes, ethylene to ethylene oxide, and ethylene glycol to glyoxal. |
| Production Methods |
Many processes are known for recovery of silver from its ores. These depend mostly on the nature of the mineral, its silver content, and recovery of other metals present in the ore. A few processes are briefly outlined below. Silver is usually extracted from high-grade ores by three common processes that have been known for many years. These are amalgamation, leaching, and cyanidation. In one amalgamation process, ore is crushed and mixed with sodium chloride, copper sulfate, sulfuric acid, and mercury, and roasted in cast iron pots. The amalgam is separated and washed. Silver is separated from its amalgam by distillation of mercury. In the cyanidation process the ore is crushed and roasted with sodium chloride and then treated with a solution of sodium cyanide. Silver forms a stable silver cyanide complex, [Ag(CN)2]–. Adding metallic zinc to this complex solution precipitates silver. Several leaching processes are known. One such process, known as the Patera process, developed in the mid 19th century, involves roasting ore with sodium chloride followed by leaching with sodium thiosulfate solution. Silver 834 SILVERis precipitated as silver sulfide, Ag2S, by adding sodium sulfide to the leachate. In the Clandot process, leaching is done with ferric chloride solution. Addition of zinc iodide precipitates silver iodide, AgI. AgI is reduced with zinc to obtain silver. The above processes are applied for extraction of silver from high-grade ores. However, with depletion of these ores, many processes were developed subsequently to extract silver from low-grade ores, especially lead, copper, and zinc ores that contain very small quantities of silver. Low grade ores are concentrated by floatation. The concentrates are fed into smelters (copper, lead, and zinc smelters). The concentrates are subjected to various treatments before and after smelting including sintering, calcination, and leaching. Copper concentrates are calcined for removal of sulfur and smelted in a reverberatory furnace to convert into blister copper containing 99 wt% Cu. The blister copper is fire-refined and cast into anodes. The anodes are electrolytically refined in the presence of cathodes containing 99.9% copper. Insoluble anode sludges from electrolytic refining contain silver, gold, and platinum metals. Silver is recovered from the mud by treatment with sulfuric acid. Base metals dissolve in sulfuric acid leaving silver mixed with any gold present in the mud. Silver is separated from gold by electrolysis. Lead and zinc concentrates can be treated in more or less the same manner as copper concentrates. Sintering lead concentrates removes sulfur and following that smelting with coke and flux in a blast furnace forms impure lead bullion. The lead bullion is drossed with air and sulfur and softened with molten bullion in the presence of air to remove most impurities other than silver and gold. Copper is recovered from the dross and zinc converts to its oxide and is recovered from blast furnace slag. The softened lead obtained above also contains some silver. The silver is recovered by the Parkes Process. The Parkes process involves adding zinc to molten lead to dissolve silver at temperatures above the melting point of zinc. On cooling, zinc-silver alloy solidifies, separating from the lead and rising to the top. The alloy is lifted off and zinc is separated from silver by distillation leaving behind metallic silver. The unsoftened lead obtained after the softening operation contains silver in small but significant quantities. Such unsoftened lead is cast into anode and subjected to electrolytic refining. The anode mud that is formed adhering to these anodes is removed by scraping. It contains bismuth, silver, gold, and other impurity metals. Silver is obtained from this anode mud by methods similar to the extraction of anode mud from the copper refining process discussed earlier. If the low–grade ore is a zinc mineral, then zinc concentrate obtained from the flotation process is calcined and leached with water to remove zinc. Silver and lead are left in leach residues. Residues are treated like lead concentrates and fed into lead smelters. Silver is recovered from this lead concentrate by various processes described above. |
| Chemical Properties | lustrous soft white metal;silvery metallic solid; insoluble in water. |
| Chemical Properties | Silver is a white lustrous metal that is extremely ductile and malleable. |
| Physical properties | Silver is located in group 11 (IB) of period 5, between copper (Cu) above it in period 4 andgold (Au) below it in period 6. Thus, silver’s chemical and physical properties are somewhatsimilar to these two group 11 partners.Silver is a soft, while, lustrous metal that can be worked by pounding, drawing througha die, rolling, and so forth. It is only slightly harder than gold. It is insoluble in water, but it will dissolve in hot concentrated acids. Freshly exposed silver has a mirror-like shine thatslowly darkens as a thin coat of tarnish forms on its surface (from the small amount ofnatural hydrogen sulfide in the air to form silver sulfide, AgS). Of all the metals, silver isthe best conductor of heat and electricity. This property determines much of its commercialusefulness. Its melting point is 961.93°C, its boiling point is 2,212°C, and its density is10.50 g/cm3. |
| Isotopes | There are 59 isotopes of silver, ranging from Ag-93 to Ag-130 with half-livesfrom a few milliseconds to a few days to 418 years. All but two of these 59 isotopes areradioactive and are produced synthetically. The two stable isotopes found in nature areAg-107 and Ag-109. These two make up 100% of the element’s existence in the Earth’scrust. |
| Origin of Name | Silver’s modern chemical symbol (Ag) is derived from its Latin word argentum, which means silver. The word “silver” is from the Anglo-Saxon world “siolfor.” Ancients who first refined and worked with silver used the symbol of a crescent moon to represent the metal. |
| Occurrence | Silver is the 66th most abundant element on the Earth, which means it is found at about0.05 ppm in the Earth’s crust. Mining silver requires the movement of many tons of ore torecover small amounts of the metal. Nevertheless, silver is 10 times more abundant than gold.And though silver is sometimes found as a free metal in nature, mostly it is mixed with theores of other metals. When found pure, it is referred to as “native silver.” Silver’s major ores areargentite (silver sulfide, Ag2S) and horn silver (silver chloride, AgCl). However, most silver isrecovered as a by-product of the refining of copper, lead, gold, and zinc ores. Although silveris mined in many countries, including the United States, Mexico, and Canada, most silver isrecovered from the electrolytic processing of copper ores. Silver can also be recovered throughthe chemical treatment of a variety of ores. |
| Characteristics |
Silver is somewhat rare and is considered a commercially precious metal with many uses.Pure silver is too soft and usually too expensive for many commercial uses, and thus it isalloyed with other metals, usually copper, making it not only stronger but also less expensive.The purity of silver is expressed in the term “fitness,” which describes the amount of silverin the item. Fitness is just a multiple of 10 times the silver content in an item. For instance,sterling silver should be 93% (or at least 92.5%) pure silver and 7% copper or some othermetal. The fitness rating for pure silver is 1000. Therefore, the rating for sterling silver is 930,and most sliver jewelry is rated at about 800. This is another way of saying that most silverjewelry is about 20% copper or other less valuable metal. Many people are fooled when they buy Mexican or German silver jewelry, thinking theyare purchasing a semiprecious metal. These forms of “silver” jewelry go under many names,including Mexican silver, German silver, Afghan silver, Austrian silver, Brazilian silver, Nevadasilver, Sonara silver, Tyrol silver, Venetian silver, or just the name “silver” with quotes aroundit. None of these jewelry items, under these names or under any other names, contain anysilver. These metals are alloys of copper, nickel, and zinc. |